What happens if you don't get an oil change for your car?

First of all, the oil will get dirty. That dirt will be carried in the oil to the smallest orifices in the engine, where it will lodge and start a clog. It will also get into the bearing surfaces and cause minute scratches which cause premature wear on those surfaces. If enough dirt gets on those surfaces, the engine will seize and fail. If you are lucky and that doesn't happen you will get molecular degradation from heat, and the oil with start to lose it's lubricity, and the same failure will occur. Either way, starving the engine of oil, burnt oil, or dirty oil, it all means catastophic engine failure, usually at highway speeds. Rule of thumb, change oil each 3000 miles and filter 6000, but I do both at 2500. Learned the hard way. Oil is cheaper than engines.What happens if you don't get an oil change for your car?
Oil needs to be changed for these reasons:





1. buildup of corrosive byproducts of combustion which could erode metal parts left to soak in it (pull a dipstick of any car that has seen long storage and note how much erosion has occurred on the portion of the dipstick that was below the surface of the oil - you may be amazed!), and





2. breakdown of additives and lubricity due to heat and mechanical stress on the oil, and





3. accumulation of dirt in the oil from debris caused by blow-by (carbonized oil and fuel), and





4. contamination cause by fuel or coolant leakage. Only the last reason is operative for a car which is not being used. This will occur only if there is a problem with the carburetor leaking fuel, or the cooling system gaskets or porosity.





If neither of these problems are suspect on a car, I see no reason to change the oil on a car which is not being driven. I know of no deterioration that occurs to oil just from sitting, at least not with modern oil. Therefore, with my older cars, which do not have the very best of oil filtration system (Packard never did adopt a full flow filter), I think the oil should be changed every 1500 miles of actual driving, and I put no time limit on that. On the newer cars, with modern spin-on full flow oil filters, I'm sure it does no damage to run at least 3000 Miles between changes. Always change the oil before storing the car, though, if it has been driven more than a few hundred miles since the last change, to avoid the corrosion problem.What happens if you don't get an oil change for your car?
The engine will eventually lock up and you'll get to go shopping for a new car.
oil is due to be changed often to protect the engine





engine oil has 3 properties here are the main 2





the first one is obviosly to lubricate any moving parts inside the engine it goes through holes so small they are invisible to the naked eye (mainly in the crankshaft) and if the oil is too dirty these holes clog up and stops the librication reaching certain parts of the engine - as time goes on the oil gets dirtier and starts clogging bigger holes - and if it gets bad enough the engine will seize due to too much friction creating too much heat and making the metal expand - all because the oil didnt reach certain parts





the other thing about oil is it helps cool the engine down by reducing friction - friction causes heat and if an engine overheats too much it will seize and not go without 拢/$1000s being spent on new parts for it





what would you rather pay


拢/$30 - 拢/$40 for an oil change


or thousands for major engine repairs





think of it this way - theres an oil filter and a service interval on every car for a reason





the other property is for keeping the inside of the engine clean
On larger engines, in the past, it wasn't as critical. The dirty oil can clog the ports in the oil gallery and ruin your engine. But, changing the oil and when depends partly upon whether it's city or highway driving.